Apparatus for burning fuel



April 19, 1949. R; E. BRESSLER APPARATUS FOR BURNING FUEL Filed March 9, 1945 Eatented Apr. 19 1949 UNITED STATES PATENT OFFICE APPARATUS FOR BURNING FUEL Robert E. Bressler, Oregon, Ill.

Application March 9, 1945, Serial No. 581,913

Claims.

This invention relates to improvements in apparatus for burning fuel and it consists of the matters hereinafter described and more fully set forth in the appended claims.

One of the objects of the present invention is to provide apparatus for burning fuel which is simple and compact in construction, so as to occupy but a small amount of space, and which is efiicient in operation in order to obtain a greater heat output from the burning fuel than has heretofore been possible, and in which both anthracite and bituminous coals may be burned.

Another object of the invention is to provide apparatus of this kind, that makes use of a relatively small fire bed which burns faster and with a greater intensity closer to the heat conducting walls of the apparatus whereby a better utilization of the heat units produced in the burning of the fuel is obtained.

Also, it is an object of the invention to provide apparatus of this kind which requires no secondary air or combustion spaces, complicated arrangement of fiues or the like for good combustion results.

Furthermore, it is an object of the invention to provide apparatus of this kind which reduces to a minimum, if not completely eliminating the discharge of smoke from the apparatus either up the stack or back through the fuel feeding means.

Again, it is an object of the invention to provide a burner arrangement in which the fuel is screw fed into the furnace past an air conduit in such manner that crowding of the fuel into the air conduit is prevented.

The above mentioned objects of the invention, as well as others, together with the several advantages thereof will more fully appear as the specification proceeds.

In the drawings:

Fig. 1 is a view partly in side elevation and partly in vertical section of an apparatus for burning fuel, embodying the preferred form of the invention.

Fig. 2 is a transverse vertical sectional view through a part of the apparatus shown in Fig. 1, as taken on the line 2-2 thereof.

Fig. 3 is a transverse vertical sectional view through another part of the apparatus as taken on the line 33 of Fig. 1.

Fig. 4 is a diagrammatic view in side elevation of the apparatus appearing in Fig. 1, on a reduced scale showing one way of providing a draft of air through the apparatus for supporting combustion therein.

Fig. 5 is a view similar to Fig. 4 showing another way of providing a draft of air through the apparatus for supporting combustion therein.

Referring now in detail to that embodiment of the invention illustrated in Figs. 1, 2 and 3 of the drawing, the improved apparatus includes a somewhat cylinder-like casting ll] of slightly tapering shape including inner and outer tubular walls H and I2 respectively separated by a water jacket space I3 that terminates at the end flanges l4 and I5 of the casting. The inner tub-ular wall ll defines a combustion chamberwhich increases in diameter from its inlet end that is associated with the flange I4 to its outlet end that is associated with the flange l5, the space in said chamber between said inlet and outlet ends constituting the combustion zone of said chamber.

The inlet from the water jacket space 13, which is located on the bottom side of the casting near the flange I4, is indicated at I6 and the outlet for said water jacket space which is located on the top side of the casting near the flange 15 is indicated at 11.

If desired a circulating pump, not shown, may be used in the pipes connected to l6 and/or H to increase the flow through the water jacket in order better to absorb the intense heat developed in the burner.

Extending longitudinally along the top of the casting is a manifold passage I8 for forced draft air and one end of said manifold opens through the flange M, as best indicated in Fig. 3, the other end of said manifold stopping short of the outlet IT for the water jacket space. A plurality of branch ducts I9, 20 and 2| respectively, each communicate at one end with the bottom of the manifold l8 to pass through a part of the jacket space to openinto the top of the combustion chamber. Preferably one side wall of each duct is disposed in a plane radially of the combustion chamber and the opposite side wall thereof is parallel therewith as appears in Fig. 3. This provides a lateral offset for each duct with respect to the combustion chamber. In the inner surface of the wall II in the vicinity of the combustion zone, before mentioned, I provide a plurality of channels l9a20a and 2 la respectively. Each of these channels communicates at its upper end with an associated duct I9, 20 and 2| respectively and extends downwardly therefrom about the interior of the wall II and then forwardly toward the discharge end of the combustion chamber. Each channel I9a-2'lla and 2 la respectively, is of a gradually reducing cross sectional area throughout its length, being of the greatest cross sectional area at that end joining its associated duct and being of the least cross sectional area at its other end where it merges into the internal surface of the wall I I, as best appears in Fig. 3.

22 indicates the fuel tube of the apparatus having an internal diameter substantially the same as that of the inlet end of the combustion chamber. Said tube is provided at one end with a flange 23 by which it is attached to the flange M of the casting H1 in any suitable manner. In said tube is a conveyor screw 24 that includes a shaft and a flight, the screw terminating at the junction of the flanges I4 and 23 as best appears in Fig. 1. The tube 22 communicates with a fuel hopper (not shown) and the screw when driven clockwise as viewed in Fig. 2, functions to feed fuel through the tube and into and through the combustion chamber toward its outlet end.

On the upper side of that end of the tube 22 associated with the flange 23 is an integral air passageway 25, which at one end opens through said flange to communicate With the manifold IS. The other end of said passageway communicates with an upright duct 26 that is offset laterally of the axis of the tube 22, as best appears in Fig. 2. The upper end of said duct 26 has a pipe 21 connected thereto and which leads from a blower or the like 27a appearing in Fig. 4 for delivering forced draft air to the duct 26. The lower end of said duct communicates with a groove or channel 26a on the inside of the tube 22. This channel extends toward the flange 23 and gradually decreases in cross sectional area toward the same.

Referring now to Fig. 2, it is pointed out that the screw conveyor turns clockwise and therefore it always functions to turn the fuel in the tube toward the bottom end of the duct 26 and therefore the tendency of the fuel to choke said duct and the passage of air therethrough is counteracted. Hence, the duct remains free and open at all times.

The flange [5 of the casting l fits in an opening 23 in one side of a closed casing 29, the closed bottom 30 of which tapers toward an opening 30a, and which has one end of a duct 3| connected thereto. The other end of said duct opens tangentially into the upper portion of the casing 32 of a centrifugal separator. The bottom end of the separator casing discharges downwardly into an ash receiving receptacle 33. A conduit 34 leads away from the top of the separator casing to carry the gases of combustion to a stack 35. If desired, a draft inducing means such as a blower 34a may be disposed in said pipe 34 as shown in Fig. for inducing a draft of air through the apparatus for supporting combustion therein instead of connecting a blower to the pipe 21 as in Fig. 4.

In the casing 29 is a bracket 36 and a shaft 31 has sliding engagement in the laterally spaced sides thereof. This shaft 3! is arranged coaxially with the axis of the casting l0. That end of said shaft extending toward the flanged end I5 of the casting I0 carries a discharge control member or disc 38 of a diameter somewhat greater than the enlarged diameter end of the combustion chamber provided by said casting. An expansion coiled spring 39 surrounds a part of the shaft between one of the sides of the bracket and a stop pin 40 that is adapted to engage the other side of said bracket. This pin is so arranged in the shaft as to prevent the member 38 from moving into that position positively closing the end of the combustion chamber.

In the operation of the apparatus, with forced draft air entering the duct 26 and with the screw conveyor in operation, the latter will feed fuel into the inlet end of the combustion chamber, combustion of the fuel taking place in the combustion zone of said chamber. Additional air to support combustion of the fuel in said zone enters each duct i9, 253 and 2i from the manifold l8 and passes downwardly of said ducts to enter the channels Eda-43a and 2 M respectively. Thus such air enters the column of fuel in the combustion zone from parts of the side and from parts of the bottom thereof. In this respect, it is pointed out that the channels wee-28a and Zia are self-cleaning, because with the disposition of the ducts as previously mentioned, fuel tends to fall away from the bottom ends of the ducts i9, 20 and 2! respectively so that it will not pile up therein to choke off the passage of air therethrough.

The movement of the fuel in the combustion chamber is such as to insure a complete burning of the fuel While in said zone so that only ash passes toward the discharge end of said combustion chamber. Under the feeding action of the fresh fuel enterin the combustion chamber, a pressure is produced by the ash upon the ash discharge control disc 38 and which will move away from said discharge end so that ash will discharge into the casing 29. The products of com bustion entering the casing 29 will pass through the duct 3! into the separator casing wherein the heavier parts of such products are separated from the lighter ones due to the forced draft air before mentioned, and the suction action of the stack 35. The separated heavier particles then pass to the receptacle 33 while the gases pass to the stack for discharge.

A part of the air entering the duct 25 by reason of the channel 26a passes into and longitudinally of the fuel in the adjacent part of the tube 22. The air so passing into the fuel prevents the gases generated in the combustion chamber from passing back into the tube 22 and producing the condition commonly known as smoke back.

The apparatus, which is small and compact in size and simple in construction, is efficient in operation, developing a greater heat output from fuel than theretofore possible in any simple burner.

Furthermore, with the arrangement described, various fuels may be burned including such wide- 1y different fuels as anthracite and bituminous coals.

While in describing the invention I have referred in detail to the form, arrangement and construction of the parts employed, the same is to be considered only in the illustrative sense so that I do not wish to be limited thereto except as may be specifically set forth in the appended claims.

I claim as my invention:

1. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to the inlet end of said combustion chamber and through said combustion zone and toward said discharge end, means operatively associated with said discharge end for the controlled discharge of said products therefrom, and means providing at least one duct of gradually decreasing cross sectional area extending partway about the internal surface of that part of the combustion chamber providing said zone for delivering forced draft air to the fuel in said zone to support combustion thereof.

2. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to the inlet end of said combustion chamber and through said combustion zone and toward said discharge end as a mass substantially filling said zone, means operatively associated with said discharge end for the controlled discharge of said products therefrom, a manifold extending longitudinally of said combustion chamber for forced draft air, and a plurality of air ducts, each extending partway about the internal surface of that part of the combustion chamber providing said zone, operatively connected to said manifold for delivering forced draft air to the fuel in said zone to support combustion thereof.

3. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, a fuel tube connected to said inlet end and having a longitudinally extending air channel in one side, means for feeding fuel from said tube :into said inlet end of the combustion chamber and through said combustion zone toward said discharge end as a mass substantially filling said zone, means operatively associated with said discharge end for the controlled discharge of said products therefrom, means for delivering forced draft air to said combustion chamber for longitudinal passage in the direction of the feed of fuel therethrough to support combustion of fuel in said zone, and means for delivering forced draft air to said channel to balance back pressure in said combustion chamber and which channel is formed to diminish in cross sectional area in the direction of the feed of the fuel through said tube to prevent the entrance of fuel gases and fuel thereinto,

4. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, a fuel tube connected to said inlet end, means for feeding fuel from said tube into said inlet end of the combustion chamber and through said combustion zone toward said discharge end as a mass substantially filling said zone, means operatively associated with said discharge end for the controlled discharge of said products therefrom, means providing a manifold for forced draft air, ducts extending partway about the internal surface of that part of said chamber providing said zone for conducting forced draft air from said manifold to said combustion zone to support combustion of fuel in said zone, and means for conducting forced draft air from said manifold to said tube to balance back pressure in said combustion chamber and formed to prevent the entrance of fuel gases and fuel thereinto.

5. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, said chamber gradually increasing in diameter from its inlet end to its discharge end, means for feeding fuel to said inlet end of the combustion chamber and through said combustion zone toward said discharge end as a mass substantially filling said zone, means operatively associated with said discharge end for the controlled discharge of said products therefrom, and means for delivering forced draft air to said combustion chamber for longitudinal passage in the direction of the feed of fuel therethrough to sup-port the combustion of fuel in said zone.

6. Apparatus for burning fuel embodying therein means providing a tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to the inlet end of said combustion chamber and through said combustion zone toward said discharge end as a mass substantially filling said zone, means operatively associated with said discharge end and mounted to yield to the pressure of said products of combustion to permit their discharge from said discharge end, said means permitting the passage at all times of the gases of combustion from said discharge end, and means for delivering forced draft air to said combustion chamber for longitudinal passage toward said discharge end to support combustion of fuel in said zone and then to :pass out through said discharge end.

7. Apparatus for burning fuel embodying therein means providing a water jacketed tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to the inlet end of the combustion chamber and through said combustion zone toward said discharge end, means operatively associated with said discharge end for preventing a too free discharge of said products therefrom while permitting a passage of the gases of combustion therefrom, a manifold for forced draft air supported from said combustion chamber, and a plurality of air ducts leading from said manifold and passing through parts of said water jacket, each duct extending partway about the internal surface of said zone and gradually decreasing in cross sectional area for delivering forced draft air from said manifold to spaced points along said zone to support combustion of fuel in said zone.

8. Apparatus for burning fuel embodying therein means providing a water jacketed tubular combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to the inlet end of the combustion chamber and through said combustion zone toward said discharge end, means operatively associated with said discharge end for the controlled discharge of said products therefrom, a manifold for forced draft air supported from said combustion chamber, and a plurality of ducts of gradually reducing cross sectional area extending partway about the internal surface of the combustion chamber at said zone, said ducts being operatively connected at one end to said manifold and at their other ends extending longitudinally of said zone toward said discharge end for delivering forced draft air from said manifold to said zone to support combustion of fuel therein.

9. Apparatus for burning fuel embodying therein a unitary casting formed to provide a water jacketed tubular combustion chamber and an integral manifold for forced draft air, said combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, means for feeding fuel to said inlet end for passage through said zone to said discharge end, said casting being formed internally with air passageways leading from said manifold and extending through the water jacket and following :partway about and then longtiud inally of the internal surface of said chamber at said zone and said air passageways having gradually decreasing cross sectional areas delivering forced draft air from said manifold to said zone to support combustion of the fuel therein and for passage toward said discharge end, and means operatively associated with said discharge end for the controlled discharge of consumed products therefrom.

10. Apparatus for burning fuel embodying therein a unitary casting formed to provide a water jacketed tubular combustion chamber and an integral manifold for forced draft air, said combustion chamber having a fuel inlet at one end, a discharge at the other end for both the consumed and the unconsumed products of combustion and a combustion zone between said ends, said casting being formed internally with air passageways leading from said manifold and extending through the Water jacket and following partway about the internal surface of said chamber at said zone for delivering forced draft air from said manifold to said zone to support combustion of the fuel therein and for passage toward said discharge end, a fuel tube connected to said inlet end, means for feeding fuel from said tube into said inlet end of the combustion chamber and through said combustion zone toward said discharge end, aforced draft air manifold mounted on said tube and connected to the manifold of 3 said combustion chamber, a duct leading from the manifold of said tube to said tube for delivering forced draft air thereto to balance back pressure of the resistance of fuel in said combustion chamber and to prevent the entrance of gases of combustion from said combustion chamber back into said tube, and means for conducting forced draft air to one of said manifolds.

ROBERT E. BRESSLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

